In astronomy, larger distances are both a blessing and a curse. They can cause issues like longer communication times, which also requires more powerful equipment, and positioning uncertainty that can affect the outcomes of measurements, especially in the outer reaches of the solar system. However, they can also be useful for a specific type of measurement called interferometry, where two systems a far distance apart can provide accurate location measurements to a third system – the same principle that GPS uses. A new paper looks at potentially using the same technique to track deep space probes rather than cars on a freeway and finds that, while it is around the same accuracy level, it is able to provide that same location data for more than double the amount of time.